Slot-punching device

Abstract

A device for punching two parallel narrow slots in a sheet of paper at 45 degrees to one edge of the sheet and spaced apart slightly less than the corner-to-corner diagonal dimension of a card which is to be attached to that sheet by inserting diagonal corner segments into the slots. The slot-punching device has a generally flat base with an adjustable stop. A lever arm pivoted on the base carries two punches with respective narrow blades for reception in the base when the lever arm is lowered. A reciprocable head on top of the lever arm is depressed to push the punch blades down into the base when the lever arm is down.

We claim: 
     
       1. A device for punching two narrow slots in a sheet with a straight edge to hold on the sheet a smaller card having a predetermined corner-to-corner diagonal dimension, said device comprising: first and second members coupled to each other for movement toward and away from each other between an apart position permitting the insertion of the sheet between them and a together position holding said sheet between them;   a stop on one of said members having a flat surface for engagement by said straight edge of the sheet;   said second member having two punches with respective narrow, flat, substantially parallel punch blades theron which extend at a substantial acute angle to said flat surface of the stop and are offset from each other both parallel and perpendicular to said flat surface of said stop, said punch blades being spaced from each other slightly less than said corner-to-corner diagonal dimension of the card;   said first member having means for receiving said punch blades when said first and second members are in said together position;   each of said punches being slidably reciprocable in said second member between a first position away from said first member and a second position projecting from said second member into said first member;   said stop being slidably adjustable on said first member toward and away from said punch blades;   spring means on said second member biasing said punches to said first position;   and a reciprocable head on said second member for displacing said punches to said second position;   said spring means comprising:   a pair of coil springs engaged between said second member and said head to bias them apart;   and a pair of coil springs acting between said second member and said punches to hold said punches against said head.   
     
     
       2. A device for punching two narrow slots in a sheet with a straight edge to hold on the sheet a smaller card having a predetermined corner-to-corner diagonal dimension, said device comprising: first and second members coupled to each other for movement toward and away from each other between an apart position permitting the insertion of the sheet between them and a together position holding said sheet between them;   a stop on one of said members having a flat surface for engagement by said straight edge of the sheet;   said second member having two punches with respective narrow, flat, substantially parallel punch blades thereon which extend at a substantial acute angle to said flat surface of the stop and are offset from each other both parallel and perpendicular to said flat surface of said stop, said punch blades being spaced from each other slightly less than said corner-to-corner diagonal dimension of the card;   said first member having means for receiving said punch blades when said first and second members are in said together position;   each of said punches being slidably reciprocable in said second member between a first position away from said first member and a second position projecting from said second member into said first member;   spring means on said second member biasing said punches to said first position;   and a reciprocable head on said second member for displacing said punches to said second position;   said spring means comprising:   a pair of coil springs engaged between said second member and said head to bias them apart;   and a pair of coil springs acting between said second member and said punches to hold said punches against said head.   
     
     
       3. A device for punching two narrow slots in a rectangular sheet of paper for holding a smaller rectangular card on said sheet at two diagonally opposite corners of the card, said device comprising: a base having a longitudinal centerline and a substantially flat top face;   an upper member above said base having a longitudinal centerline which registers with the longitudinal centerline of the base, said upper member having a first narrow opening on the bottom spaced from said centerline of said upper member on one side thereof and elongated at an angle of substantially 45 degrees to said centerline of said upper member, said upper member having a second narrow opening on the bottom spaced from said first opening lengthwise of said upper member, said second opening being spaced from said centerline of said upper member on the opposite side thereof and being elongated substantially parallel to the direction of elongation of said first opening, said openings being spaced apart slightly less than the distance between said diagonally opposite corners of the card;   a stop member slidably adjustable on the base along said centerline of base, said stop member presenting a flat vertical surface above said base extending perpendicular to said centerline of the base on opposite sides of said centerline of the base;   said upper member being coupled to said base for movement down toward said base and up away from said base, said upper member when positioned up away from said base permitting a sheet of paper to be inserted on top of the base with one of its edges against said flat surface of the stop member;   and first and second punches on said upper member, said first punch having a sharp-edged blade which is reciprocable up and down in said first opening in the upper member, said second punch having a sharp-edged blade which is reciprocable up and down in said second opening in the upper member.   
     
     
       4. A device according to claim 3 wherein said upper member is a lever arm pivotally supported on said base. 
     
     
       5. A device according to claim 4 wherein: each of said punch blades is slidably reciprocable up and down in said lever arm between a raised position in which it is above the bottom of the lever arm and a lowered position in which it projects down below the bottom of the lever arm; and further comprising:   spring means biasing said punches to said raised position;   and a head reciprocably mounted on top of said lever arm for movement up and down with respect to the lever arm, said head being coupled to said punches to move said punch blades down to said lowered position when the head is pushed down on the lever arm.   
     
     
       6. A device according to claim 5 wherein said means for receiving said punch blades is rubber-like material on said first member. 
     
     
       7. A device according to claim 5 wherein said spring means comprises: a pair of coil springs engaged between said lever arm and said head to bias them apart;   and a pair of coil springs acting between said lever arm and said punches to hold said punches against said head.   
     
     
       8. A device according to claim 5 wherein: said punches are fastened to said head; and said spring means is a resilient and compressible pad on said lever arm engaging said reciprocable head.